EML4550 - Engineering Design Methods

1. EML4550 - Engineering Design Methods Lecture topics: The ‘front end’ in the design process Concept Development - Identifying, documenting, and classifying customer needs Hyman: Sections 2.1 - 2.4 Dym and Little: Section 3.1 - 3.3 Ulrich and Eppinger: Chapter 3 Dieter: Chapter 2

2. Phases of the design process • Concept development • Identify customer needs, gather information on competition or possible alternatives, generate and evaluate alternate concepts, select concept, define form and function of the artifact. [feasibility study] • System-level design • Determine system architecture (configuration) as well as all sub-systems and respective interfaces, produce system layout and specifications for the system and each sub-system • Detailed design • Complete and final specification of the system, including geometry, materials, tolerances, etc. (drawings), complete and final manufacturing process specification. • Testing and refinement • Review design, build prototype (if appropriate), alpha and beta prototype. • Production ramp-up and delivery • Production line checked and refined, product ‘launch’

3. Concept development: the ‘front end’ Hyman Ch. 2.2 • Identify customer needs • Establish target specifications • Analyze competitive products • Generate concepts (alternatives) • Evaluate concepts (trade-off) • Select concept • Refine specification • Economic analysis (part of trade-off) • Project planning Problem definition Tools introduced: QFD, performance metrics Ch. 2.3, 2.4, 2.5, 2.6 Balance between Cost, performance, time Justification for project After a thorough design review

4. Establish Target Specs Generate Product Concepts Select Product Concept Refine Specs Plan Design/ Development Project Perform Economic Analysis Analyze Competitive Products Concept Development Diagram Identify Customer Needs Mission Statement Action Plan

5. Customer Needs vs. Product Specifications • Subtle but important differences between customer needs and product specifications • Customer views a product without any technology bias • Customer uses product without knowledge of design process or internal sub-systems • It is important to always distinguish when a specific need is driving a feature, or when a designer is introducing an assumption in order to arrive at a specification

6. Identifying Customer Needs • Objectives of this phase: • Ensure product is focused on customer needs • Identify explicit needs as well as hidden (latent) needs • Provide factual basis for product specification • Create an archival record of this phase of the process (customer interactions, needs identified, etc.) • Ensure no critical customer need is overlooked • Develop common understanding of customer needs within the design team

7. Steps in Identifying Customer Needs • Step 1: Define the scope of the effort • Step 2: Gather raw data from the customers • Step 3: Interpret raw data in terms of customer needs • Step 4: Organize the needs into a hierarchy • Step 5: Establish the relative importance of the needs • Step 6: Reflect on the results of the process

8. Step 1: Define the scope of the effort • Brief (one-sentence) description of the product • Key business goals • Target market for the product • Who are the customers? • Assumptions that constrain the development effort • “Rules of engagement” • Stakeholders • Besides the customers, who else is on the development chain? Marketing chain? Service chain?

9. Step 2: Gather raw data from the customer • Interviews • Meeting with single customer, at customer’s premises, under 2 hours • Focus Groups • Group of about 10 customers, videotaped and documented, Q&A, etc. • Customer feedback (surveys, complaints) • Observing the products in use • Using existing products

10. Step 2: Gather raw data from the customer • Choosing customers • Who is the real customer? User? Lead users? • Eliciting customer needs data • Go with the flow • Use visual stimuli and props • Do not introduce developers ‘bias’ or preconceived notions • Have a customer demonstrate the product • Be alert and open minded • Watch for non-verbal communication • Document Customer Interaction • Notes, pictures, audio, video

11. Step 3: Interpret raw data in terms of customer needs • Express the needs in terms of what the product has to do, not how it might do it • Express the needs as specifically as the raw data (no data loss) • Use positive, not negative, phrasing whenever possible • Express the needs as attributes to product • Avoid “must” and “should”, do not bias needs priority • Object: A “needs” set as articulated by the design team based on customer interaction

12. Step 4: Organize the needs into a hierarchy • Write needs in individual cards • Eliminate redundant needs • Group needs according to similarity • Choose a label for each group • Consider creating ‘supergroups’ (2 to 5) • Review and edit the organized needs statements

13. Step 5: Establish the relative importance of the needs • Separate primary (e.g., “must have”) from secondary needs (e.g., “would be nice to have”) • Keep in mind design trade-offs to come • Begin to quantify ‘cost’ of each need and ‘desirability’ of each need • Methods to prioritize • Team consensus • Further customer surveys

14. Step 6: Reflect on the results of the process • Has the team interacted with all relevant stakeholders? Customers? Corporate departments? • Have we gone beyond the needs fulfilled by existing products? Latent needs? • Need for follow up interviews? • Need to include customers in development effort? Who? • Did we learn something new? Surprises? • Can this process be improved in the future?

15. Example: Coupling mechanism Needs Assessment Our objective is to design a mechanism that will enable the rotor to break away from the gear pump shaft when the rotor seizes and then re-engages when the rotor torque falls below a certain level, while maintaining the timing of the rotor upon re-engagement.

16. Example: Saltwater flume cooling Customer Needs Assessment We have had met with Dr. Thistle on the Florida State University campus as well as the Marine Research Facility at Alligator Point. In our interviews the client has stated the following item of which the Temperature regulator would have to perform: Client Needs and Wants Statement Be able to set temperature on controller before or during operation and temp maintain within 2 degrees of setting Cooler must be environmentally inert No major changes to existing equipment Can be detached and replaced if setup must be moved Exposed metal surfaces must be marine alloys Must be long lasting and reliable Easily to operate System must be safe to operate Should be able to manually shut off All electronics and electrical wiring should be marine quality System components easily replaced or fabricated at local hardware stores or in machine shop Design should be done as quickly as possible Design should have minimum cost or have features and speed of availability to -make worthwhile

17. Example: Yeast Cultivator

18. Example: Web-based flow experiment

19. Implications to Projects • Arrange early meeting with “customers” • Prepare questions for the meeting • Keep meeting short and focused • Document feedback from the meeting • Organize and document “customer needs” • Include all findings in third deliverable (needs assessment and basis for specification) • Start to flesh out scope of project in conjunction with “customer”